Transformations of empty Cu I4 core to Cu I2Cu II2O and Cu I6S cores via oxide and sulfide insertions

Abstract

[Cu₄(L^Rh)₄]⁸⁻ ([1]⁸⁻; L^Rh = Δ-[Rh(L-cysteinate)₃]³⁻), with an empty tetrahedral {Cu^I₄}⁴⁺ core, was converted to [Cu₄O(L^Rh)₄]⁸⁻ ([2]⁸⁻), with a mixed-valent {Cu^I₂Cu^II₂O}⁴⁺ core, in aqueous NaOH. A solid sample of the latter compound was converted back to [1]⁸⁻ by heating under vacuum, while treatment of [1]⁸⁻ with aqueous NaSH caused conversion to [Cu₆S(L^Rh)₄]⁸⁻ ([3]⁸⁻), with a stable octahedral {Cu^I₆S}⁴⁺ core.